If you take a look at the home.php file in the Welcome area, can you see and understand how everything is setup? Do you see how the div containers wrap around the widgets? If so, then you just need to place it inside of its own div. You may need to also add a custom class for it as well.
It’s a mix of php and html, so if you’re not familiar with with the basics of either one then it will probably look confusing. I assume you’re pretty good with HTML/CSS from looking at your site…..but let me know if you need more assistance.